Can you look through your /var/log/gdm/ files? There should be one that is not using failsafe, and might have an error message or backtrace that indicates that the mga driver crashed. There is nothing in this mga log.
** Attachment added: "mga-Xorg.0.log" http://launchpadlibrarian.net/21923349/mga-Xorg.0.log -- Can not get 1024x768 video mode by undetected monitor and Matrox G100 8MB graphics adapter https://bugs.launchpad.net/bugs/319363 You received this bug notification because you are a member of Ubuntu Bugs, which is subscribed to Ubuntu. -- ubuntu-bugs mailing list ubuntu-bugs@lists.ubuntu.com https://lists.ubuntu.com/mailman/listinfo/ubuntu-bugs